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Biomedical subjects

C Monge

Publications and source records attributed to C Monge.

At least 37 records · Page 2Linked to original sources
PubMed1991

A genetic response to high altitude hypoxia: high hemoglobin-oxygen affinity in chicken (Gallus gallus) from the Peruvian Andes.

A population of chicken (Gallus gallus) from the Peruvian Andes (4,000 m) carrying a high hemoglobin-oxygen affinity has been identified. This property remained stable after over 1 year residence at sea level and was transmitted to the descendants born at sea level. Chicken were introduced in South America during the Spanish conquest and therefore their adaptation time to high altitude is less than 500 years. This finding shows that a genotypic change in hemoglobin function can occur in an extremely short evolutionary time and leads to some reflections on the high altitude adaptation of the mammals that migrated to South America during the great Plio-Pleistocene interchange.

Altitude↗
PubMed1987

Shell conductance, daily water loss, and water content of Andean gull and Puna ibis eggs.

Characteristics of Andean gull (Larus serranus) and Puna ibis (Plegadis ridgwayi) eggs laid at 4,400 m in the Peruvian Andes were studied to determine how the conflicting requirements of maximizing O2 availability to the embryo while minimizing excessive losses of water vapor and CO2 have been met by avian populations breeding at high altitudes. Egg masses, linear dimensions, and surface areas of these montane eggs were similar to those of Heermann's gull (Larus heermanni) and glossy ibises (Plegadis falcinellus), but conductance to water vapor (GH2O, standardized to 760 torr) of Andean gull and Puna ibis eggs averaged 74.5% and 68.4%, respectively, of lowland values. The difference in GH2O of Andean gull eggs was caused primarily by a reduction in the number of pores per egg; both an increased shell thickness and a smaller number of pores reduced GH2O of Puna ibis eggs. Since the reduction of GH2O of montane eggs did not fully compensate for the change in barometric pressure (59% of sea level) and the increase in gaseous diffusion coefficients at 4,400 m, the "effective" conductance of the eggs at that altitude was greater than at sea level. Therefore, the eggs lost substantially more water during incubation than did lowland eggs. The modifications in eggshell characteristics of montane eggs may have resulted from selection to increase O2 availability to the embryo.

Altitude↗
PubMed1986

Maternal hypoxic ventilatory response, ventilation, and infant birth weight at 4,300 m.

To test the hypothesis that increased hypoxic ventilatory responsiveness (HVR) raised maternal ventilation and arterial oxygenation during high-altitude pregnancy and related to the birth weight of the offspring, we studied 21 residents of Cerro de Pasco, Peru (4,300 m), while eight of them were 36 +/- 0 wk pregnant and 15 of them 13 +/- 0 wk postpartum. HVR was low in the nonpregnant women (mean +/- SE shape parameter A = 23 +/- 8) but increased nearly fourfold with pregnancy (A = 87 +/- 17). The increase in HVR appeared to account for the 25% rise in resting ventilation with pregnancy (delta VE observed = 2.4 +/- 0.7 l/min BTPS vs. delta VE predicted from delta HVR = 2.6 +/- 1.7 l/min BTPS, P = NS). Hyperoxia decreased ventilation in the pregnant women (P less than 0.01) to levels similar to those measured when nonpregnant. The increased ventilation of pregnancy raised arterial O2 saturation (SaO2) from 83 +/- 1 to 87 +/- 0%, and SaO2 was correlated positively with HVR in the pregnant women. The rise in SaO2 compensated for a 0.9 g/100 ml decrease in hemoglobin concentration to preserve arterial O2 content at levels present when nonpregnant. Cardiac output in the 36th wk of pregnancy did not differ significantly from values measured postpartum. The increase in HVR correlated positively with infant birth weight. An increase in HVR may be an important contributor to increased maternal ventilation with pregnancy and infant birth weight at high altitude.

Adult↗
PubMed1985

Acute mountain sickness: critical appraisal of the Pariacaca story and on-site study.

The physiological and medical literature on the description of acute mountain sickness by Father Acosta in the Peruvian Andes shows many historical misconceptions and clinical misinterpretations. A recent paper by Gilbert (1983) not only contains these traditional misinterpretations but also adds geographical errors in the description of the area where Acosta described his sufferings. In view of these facts the authors have made a review of the old and modern writings on the so called Pariacaca story and during an on-site visit to the area of Pariacaca have taken actual measurements of distances, altitudes and geographical locations which they hope will put this story in the context of historical and scientific objectivity.

Acute Disease↗
PubMed1985

Normal whole blood Bohr effect in Peruvian natives of high altitude.

Measurements of whole blood O2 affinity were made with an automatic technique that allowed recording of O2 saturation continuously over a range of PO2 of 1 to 150 torr at constant pH and PCO2 with fresh samples of blood obtained from 5 natives of high altitude at Morococha, Peru (altitude, 4540 m). The results were not significantly different from those obtained with controls living at sea level with regard to the dlog P50/dpH slope at constant PCO2 or at constant base excess. Both results also agree with previous studies with normal sea-level blood. Thus earlier claims of an increased Bohr in Peruvian high-altitude natives is not supported.

Adult↗
PubMed1981

[Evaluation of various hematologic parameters in Andean miners (Morococha-Peru 4560 m)].

In other Author's previous studies refer that prolonged CO exposure, as chronic altitude exposure, causes marked increases in Hb and Htc levels. We had intended to study these hematologic changes on three non-smokers' group : Miners of the Andes working at CO exposure ambients, Residents and European Subjects living a. s. l. and exposed at 4560 m. Statistical analysis, according with literature, has shown significant difference in the three groups' Hb and Htc ratio, in comparison with sea level control values. We had moreover observed that HbCO of the Miners' group reached, sometimes, 8, 2% values. It does not seem, however, that the higher HbCO levels noted in the Miners' group are sufficiently elevated for producing a further increase in Hb and Htc ratio compared to the other two control group.

Adult↗
PubMed1981

[Blood sugar and the hematocrit: relation to acclimatization at 4560 m. altitude].

We had intended to study the relation between glycemia and hematocrit during high altitude acclimatization (Morococha, Peru-4560 m) and to observe if, subsequently to an increase of hematocrit, glycemia should become lower. From obtained results upon 176 hematologic observations of glycemia, hematocrit, hemoglobin and erythrocyte production, on 38 healthy European subjects (27-58 years aged), it doesn't result, from the first analysis, the existence of this relation. We reserve ourselves, in any case, to accomplish further tests, such as insulinemic dosage for evaluating pancreatic activity.

Adult↗
PubMed1978

Ecology and health.

Health is commonly conceived as having fixed and universal aims, while conditions interposed by environmental and cultural conditions are often ignored or at least shunted to one side. Rejecting this point of view, the author asserts that health in any society should be defined in terms of ecological reality--that is, in terms of the cultural and environmental variables affecting the population. He also notes that acceptance of this concept does not imply perpetuation of a natural but static situation. Rather, it implies searching for ways to improve the situation without necessarily striving for international goals that may be unsuitable or impossible to achieve. The concept also implies that we should ask how to define a satisfactory health level for a given set of conditions--and then consider how to achieve that level. The search for answers to these questions and subsequent programs based on the results will require a multidisciplinary approach. Within this context two PAHO facilities, the Pan American Center for Human Ecology and Health (ECO) and the Pan American Center and Engineering and Environmental Sciences (CEPIS), can provide strong support for activities in the Americas. Specifically, ECO is in a good position to collaborate on ecological planning, model-building, and research evaluation, while CEPIS is geared to provide advice and assistance in the key field of environmental sanitation.

Cultural Characteristics↗
PubMed1977

[The teaching of internal medicine in the forming of the physician].

This paper was presented as a working document to the Second Meeting of the PAHO/WHO Program of Textbooks for the Integrated Teaching of Internal Medicine and its Specialties (Washington, D.C., 13-18 December 1976). The need to place the medical student in his environment from the first as an active member of the health team is stressed, and several considerations about the usual obstacles to this proposal are advanced. Reference is made to the subject of curricular integration as related to the length of medical studies and to the traditional use of the hospital in the teaching of internal medicine. The second part of the document reports on the results of the PAHO survey on how internal medicine is taught in Latin America, in which 84 faculties and schools in 15 countries of the Region participated.

Education, Medical↗